Melting ice could alter climate

AS MELTING Greenland glaciers continue to pour ice into the Arctic Ocean, we have more than the rising seas to worry about, scientists have said.

A new study suggests that if it gets large enough, the influx of fresh water from the melting ice sheet could disrupt the flow of a major ocean current system, which in turn could dry out Africa’s Sahel, a narrow region of land stretching from Mauritania in the west to Sudan in the east.

The consequence could be devastating agricultural losses as its climate shifts in the future. “The implications… bring home just how sensitive livelihoods are in this region to climatic change,” said Christopher Taylor, a meteorologist at the Centre for Ecology and Hydrology in the UK.

The study, published in the journal, Proceedings of the National Academy of Sciences, uses a climate change model to investigate the influence of different amounts of ice loss from Greenland, corresponding to different amounts of global sea-level rise, on the western Sahel’s climate system. Previous studies have suggested that this region may be vulnerable to disruptions in the ocean.

The idea is that large volumes of meltwater from Greenland have the potential to slow down a major system of ocean currents known as the Atlantic Meridional Overturning Circulation, or Amoc. Experts have described it as a kind of giant conveyor belt that carries warm water from the equator to the Arctic and cooler water back down south. This helps regulate climate in the Atlantic region.

As glaciers in Greenland melt, scientists think that the influx of cold, fresh water could cause this conveyor belt to slow down and could alter weather patterns, with major consequences for western Africa